VR 16 HH is a high-hardness, pre-hardened mould steel developed for demanding applications where superior strength, wear resistance, and dimensional stability are required. It belongs to the high-performance family of tool steels used in the die-casting, forging, extrusion, and high-pressure plastic moulding industries. The “HH” in VR 16 HH typically represents High Hardness, indicating its elevated strength level compared to standard grades.

VR 16 HH is usually supplied in a pre-hardened condition ranging between 38–44 HRC, depending on manufacturer specification. This eliminates the need for additional heat treatment, helping reduce machining time and avoiding distortion. Its alloy composition is optimized to deliver a balance of toughness, hardness, and thermal stability.

Key Characteristics of VR 16 HH

1. High Hardness & Strength

VR 16 HH is engineered for applications that require superior strength and long tool life. Its hardness range (38–44 HRC) provides excellent resistance to abrasion, indentation, and mechanical fatigue.

2. Excellent Toughness

Higher toughness allows the steel to withstand heavy loading, impact stress, and sudden pressure changes without cracking or deformation. This makes it reliable for complex tooling environments.

3. Good Machinability for Its Hardness Range

Even at high hardness, VR 16 HH maintains good machining behaviour. With proper tooling, it can be efficiently milled, drilled, EDM-cut, and ground.

4. Superior Wear Resistance

The alloy composition is designed to resist wear caused by contact pressure, friction, and heat cycles. This is especially beneficial for:

a. Die-casting dies

b. Extrusion dies

c. Forging tools

d. Heavy-duty injection moulds

5. Good Heat Resistance

It retains its strength at elevated temperatures, allowing use in processes involving:

a. Melted aluminium

b. High-pressure molten material flow

c. Thermal cycling environments

6. Suitable for Nitriding

The grade can be nitrided to achieve surface hardness 58–62 HRC, significantly improving its resistance to wear, galling, and heat checking.

7. Good Weldability

Maintenance welding, repair welding, and engineering modification can be performed with proper procedure. Its alloy purity helps maintain stable hardness around welded zones.

Typical Applications

1. High-pressure die-casting dies

2. Forging dies & tooling

3. Extrusion tooling

4. Blow moulds requiring high strength

5. Heavy-duty mould bases

6. Injection moulds with abrasive plastics

7. Components exposed to continuous thermal cycling

Summary

VR 16 HH is a high-hardness, tough, and wear-resistant steel grade designed for heavy-duty industrial tooling. Its pre-hardened structure, excellent heat stability, and strong mechanical performance make it ideal for die-casting, forging, and high-load mould applications. The combination of strength, machinability, and durability ensures long mould life and consistent performance even under harsh operating conditions.